Stethoscope.



' n No. 821,315. PATENTED MAY 22, 1906.

O. M. ROOT. STETHOSGOPE.

APPLICATION FILED SEPT. 14, 1905- UNITED sTATEs PATENT OFFICE.

CHARLES M. ROOT, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO FREDERICK DITTMAR AND FRANK CLAUS, OF PHILADELPHIA, PEN N- SYLVANIA, TRADING AS PENN SURGICAL MFG. CO.

STETHOSCOPE.

Specification of Letters Patent.

Patented May 22, 1906.

Application fi led September 14, 1905. Serial No. 278,373,

To all whom it may concern.-

Be it known that I, CHARLES M. RooT, a citizen of the United States,residing at the city of Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Stethoscopes, of which the following is a specification.

My invention has relation to stethoscopes and in such connection it relates to theparticular constructive arrangement of the soundtransmitting device so as to permit of a distinct deflection of sound produced by subdividing and amplifying the same anterior to its deflection from the device.

The principal objects of my invention are, first, to provide a stethoscope with a soundtransmitting device having depressions in the face of the same for collecting sound and with a projection between the depressions so arranged as to deflect the sound presented to the depressions by subdividing and amplifying the same prior to its deflection from the transmitter of the device, and, second, to provide the stethoscope-base with contracted or tapering deep depressions having openings therein which form continuations of said depressions and with a central conical projection so arranged as to permit of unobstructed exit of the subdivided sound from the base and with tubular extensions to receive and support flexible tubing of the device.

The nature, characteristic features, and scope of my present invention will be more fully understood from the following description, taken in connection with the accompanying drawings, forming part hereof, in which Figure 1 is a side elevational view of a stethoscope embodying main features of my said invention. Fig. 2 is a detail view, enlarged,

illustrating in front elevation the base of the,

sound-transmitter of the device provided therein with two deep depressions separated from each other by a conical projection and showing also flexible tubing connected with tubular extensions of said base. Fig. 3 is a similar view illustrating in rear elevation the base of the stethoscope with its tubular extensions projecting therefrom and with the flexible tubing engaging the same; and Figs. 4 and 5 are cross-sectional views of the soundtransmitting means of the device on the lines 4 4 and 5 5 of Fig. 1, illustrating the dishshaped base having deep depressions with openings therein separated by a central conical projection and with tubular outside extensions forming continuations of said openings for engaging flexible tubing of the device therewith.

Referring to the drawings with reference to Fig. 1, A is the soundtransmitter, to which are secured flexible tubes B, engaging the rigid ear-tubes C, provided at their free ends with the usual earpieces D, forming the sound-receiver of the stethoscope. The eartubes C are movably connected with each other by a leaf-spring E, provided with tubular extensions E, which by surrounding the ear-tubes C connect the spring E to the same. The sound-transmitter A, forming the subject-matter of the present application, consists of a shallow dish-shaped base a of annular outline, the inner face a of which is concave and the outer face a convex in cross section. The face a of the base a is pro vided with a diaphragm b, resting on the in ner perimeter of the base a and removably held in position by an internally threaded ring 0, which engages the threaded portion a of the base a, as shown in Figs. 4 and 5. In the base a, at the deepest part are arranged depressions a and a annular at their outer periphery and concentric to the perimeter of the base a. Between the depressions a and a is arranged a central conical projection a terminating with its highest part (1 adjacent to the diaphragm b, but at such distance from the same as to permit of free vibration and am plification of sound in the transmission in the direction of the deep perforated depressions a and a in the base of the device. As shown in Fig. 4, from the highest part a, of the projection a it gradually slopes downward and merges at opposite ends 1n the face a of the base a, while toward the depressions a and a the same slopes more abruptly and merges into openings a and a in the deepest portion of said depressions a and a. The

openings at and a are in the central horizontal axis of the base A, and from the same the depressions a and a gradually merge into the face of the base a, as shown in Figs. 2, 4, Sounddeflected and amplified in its and 5.

transmission through the diaphragm I) traveling along the face of the base a is conveyed in a subdivided condition into the deep depressions a and a to and through the openings a and a to the tubular extensions a and thence through the flexible tubing B to the earpieces D by means of the ear-tubes C' By the described arrangement of perforated depressions in the base and of the projection thereof the faintest sound deflected in transmission by means of the diaphragm b is quite distinctly audible at the earpieces D, owing to the absence of obstructions in the path of travel of the sound-vibrations. Moreover, the division of the sound-vibrations is accomplished without deadening efiect, which occurs when sound-vibrations are conveyed in the path of each other prior to entrance into openings, as is the case in instruments hitherto provided for such purposethat is, the souncLvibrations emanating from the diaphragm b are clearly and distinctly audible to a far greater degree than has heretofore been possible in Stethoscopes as constructed prior to my said invention.

Having thus described the nature and obj ects of my invention, what I claim as new, and desire to secure by Letters Patent, is

1. A stethoscope, consisting of a base provided with deep depressions having openings and separated -from each other by a central projection, a diaphragm removably secured to said base, tubular extensions connected with the openings of said base and flexible means connected therewith and by tubing with earpieces, substantially as and for the purposes described.

2. A stethoscope, consisting of a base provided with tapering depressions having openings therein, said depressions separated from each other by means of a conical projection, a diaphragm removably secured to said base, and tubular means connected with the openings of said base and with earpieces, substan tially as and for the purposes described.

In testimony whereof I have hereunto set my signature in the presence of two subscribing witnesses.

CHARLES M. ROOT. WVitnesses:

l/VILHELM 'VOGT, TnoMAs M.SMIT1I. 

